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Old February 13th 17, 10:30 PM posted to sci.astro.research
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Default Cosmic Energy Budget, vs time

Questions (below) relate to total energy (sum of terms) in this paper:

In the paper, "The Cosmic Energy Inventory" Fukugita / Peebles, They
created a list of all known forms of energy within the universe today.

(They said, "We present.............at the present epoch".........which
I take to mean, correct me if wrong, they are listing all forms of
energy that exist within the entire modern (co moving with us)
universe.)

For this question I ignore all "Dark" forms of energy and focus only on
the 5% that is in forms we have detected such as neutrinos, baryons, EM
radiation.

Ignoring Dark mass and Dark energy, the total universe energy inventory
is:

1.00 - 0.954 = 0.046 and the primary 4 constituents a

Neutrinos = 0.00126
Baryon Rest Mass
Warm Intergalactic plasma = 0.045
Intracluster plasma = 0.0018
Main Sequence Stars spheroids and bulges, disks and irregulars
0.0015 + 0.00055 = 0.00205

These 4 components combined constitute 0.05011.
(This is greater than 4.6%, so error bars must be the culprit
unless I did the addition wrong.)

At any rate, this 100% of known stuff (5% if we were to include dark
stuff) must total to the same value no matter what age of the universe I
consider, right?

In other words, section 7 is post stellar radiation. section 6 is post
stellar nuclear binding energy.

And the energy associated with those two categories must have originally
been associated with the section 3, baryon rest mass.

ie, fusion energy release reduced baryon mass and increased radiation
and nuclear binding energy. But the total energy (if I sum all of the
forms in addition to these 3) at previous epochs of our universe would
be the same as the total today, Right?

In other words, 100% of this 5% of stuff we know about, has always been
and always will be, 100%. The quantity of energy in each category may
shuffle around a little, but the total will remain unchanged.

So if I want to make a plot of this inventory as a function of age of
the universe, then I should make certain to track the sum of the
individual components to make sure they always sum to 100% of what 100%
is today, Right?

Thanks,

rt